COAL

Tim

Tim

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6.5 Creedmore
Hornady 140 ELD-M

When I changed my jump from 0.070” (matches factory load) to 0.020”, my groups and SDs both improved dramatically. I really really like the results I got with this load.

BUT...I noticed I was having difficulty feeding from the mag, maybe once every 4-5 rounds. I chalked that up to not running the bolt hard, babying it. If I ran the bolt with authority, I had no issues.

To be honest, I never checked the COAL as I was focused on the base to ogive measurement. Turns out the COAL is 2.895, which is 0.070” over the 6.5CM spec.

Do I NEED to go back to a shorter COAL to be safe? Or can I run with being 0.070” over spec and deal with the mag feed issue?


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SAAMI spec max COAL is for ammunition manufacturers to stay within so firearms and magazine manufacturers know what to design around and visa versa. You are safe.

I measured the magazine interior length to know what my max COAL is, then measured ogive to tip of a sample of bullets and subtracted three times the variance just to give me room for error and different lots and now just worry about controlling CBTO variation. I got lucky that max CBTO group size and .020" deeper give the same group size so I just target the middle and run with it.

The only thing to worry about is whether your "running the bolt with authority" seats your bullets any deeper.
 
Tim said:
6.5 Creedmore
Hornady 140 ELD-M

When I changed my jump from 0.070” (matches factory load) to 0.020”, my groups and SDs both improved dramatically. I really really like the results I got with this load.

BUT...I noticed I was having difficulty feeding from the mag, maybe once every 4-5 rounds. I chalked that up to not running the bolt hard, babying it. If I ran the bolt with authority, I had no issues.

To be honest, I never checked the COAL as I was focused on the base to ogive measurement. Turns out the COAL is 2.895, which is 0.070” over the 6.5CM spec.

Do I NEED to go back to a shorter COAL to be safe? Or can I run with being 0.070” over spec and deal with the mag feed issue?


View attachment 140643

View attachment 140645
Click to expand...

Go to shortactionprecision.com and order the accurate mags WITHOUT the binder plate. They're the ones I use, gives you more room, as my 6.5 loads will not fit in a standard metal AI mag.

Or, google binder plate removal. Its not hard and cheaper than new mags.

https://www.shortactionprecision.co...l/products/accurate-mag-308-10-round-long-mag
 
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jmccracken1214 said:
Go to shortactionprecision.com and order the accurate mags WITHOUT the binder plate. They're the ones I use, gives you more room, as my 6.5 loads will not fit in a standard metal AI mag.

Or, google binder plate removal. Its not hard and cheaper than new mags.

https://www.shortactionprecision.co...l/products/accurate-mag-308-10-round-long-mag
Click to expand...

BurnedOutGeek said:
That ^

Basically drill out the rivets and knock out the plate.
Click to expand...

Negative ghost rider....Tikka mags, not AICS. That’s the only thing I don’t like about this rifle.
 
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jmccracken1214 said:
10-4. That sucks about mags man. But not a huge deal. I had a savage Lrp and it shot great with the bullets seated for their factory mag.

Your rifle shoots nasty good for production rifle
Click to expand...


I'll likely bump the loads back just enough so the tip is inside that feed ramp looking dealio.
 
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